Electrolytic rust removal:
http://youtu.be/R5I5WBG5HPw

On my restoration of the 2cv i used this method for some pieces that were so rusty i couldnt get a brush on.

So i did the panel that is underf the front window and the rear lights panel. It is a good method though it needs a lot of amp to do this quick. Except this the remaining water is good for plans trees etc.

Now at the ending i found another method with a cleaning liquid that we use on our houses that does the same work but faster without electricity.The dissadvantage on this is that you have to through the water with the liquid not on the ground.

Hi Pavlos,what liquid is it that you use?

it called VIAKAL and we use it in our bathrooms to clean the metal and all the other surfaces that the water leaves traces and salt.
it is very efective. i ll take some pictures in about 1 hour from now

I've used this quite a few times with some success. If you google it or search youtube there are plenty of how-tos, most of them recommend using washing soda (sodium carbonate) which you might find in a large supermarket, DIY shop, or hardware place amongst the cleaning products.

It's not this however that removes the rust, it's only added to the water to make it more conductive, and you don't need much, I think about a table spoon per gallon(5 litres) is recommended. The rust is removed by the electricity actually reversing the rusting process, it splits the iron oxide back into iron and oxygen, the oxygen bubbles to the surface and the iron is left on the piece as grey/black deposits, these need wire brushing off afterwards but they come off very easily. The piece of sacrificial steel will be eroded away, so be very careful to get the wires connected the right way around, or the piece you intended to de-rust will come out with holes in it.

Any DC power source is suitable, but the higher it's out-put the quicker the process, a basic battery charger is perfect, even better if it has a built in ammeter, as then you know it's working.

Some of the guides warn about the mixture of hydrogen and oxygen given off being a fire risk. Being the curious type I tried putting a lighter to the bubbles on the surface of the water, I got a couple of small 'phut' and 'pop's but nothing interesting. Perhaps if you collected the mixture in a bin bag it might be more dramatic, but overall I wouldn't be too concerned.

Will this electrolytic rust removal with a standard 12 battery charger and a big bucket (or something) also work on the rims of a 2CV? Does anybody of you have any experiende with this?

It will work on any rusty iron or steel. I don't know what effect it will have on the rust hidden in seams though. I use a plastic dustbin, but any large non-metallic container will do.

It will work at any metalic suface and it will convert rust even in hidden spots. The only thing that you don't put in the bucket is stainless steel cause it produce dangerous toxic gas and the remaining water is dangerous and toxic.

It is also very important that the surfase that you ll put with the + line in te water to be bigger than the surfase of the metal that you want to clean.

Concernign this cleaning liquid




And you can see the result after one night in the liquid




As you can notice the down left corner left out of the water . I think you can tell the diffference.

Used this method on a set of landrover wheels using a small inflateable paddling pool as a container, worked extremely well just be prepared to paint or rust proof the item straight away as it will start to rust again immediately.

As Pavlos mentioned, there are some issues about using stainless steel as the 'other' piece of steel in the water. I have seen some guides that recommend using it as it doesn't erode and turn the water into rusty soup, but I have seen plenty of other guides that warn against it due to the chemicals produced, I've seen chromium salts mentioned. But knowing how much of the internet is rumour and chinese whisper, I'd be interested to hear from a chemist about exactly what is produced and how dangerous it is.

The reason I'm wondering is that it occurred to me that it could be possible to erode the mild steel bits out of 2cv front window frames, without damaging the stainless frame, rather than the traditional method of allowing the mild steel to make a rusty streak down the door. So anyone know any chemists?